> ## Documentation Index > Fetch the complete documentation index at: https://docs.rhinestone.dev/llms.txt > Use this file to discover all available pages before exploring further. # Rhinestone > Self-custodial stablecoin infrastructure for fintechs. Rhinestone is self-custodial stablecoin infrastructure for fintechs. Give users an account they control, help them fund it, and move value across chains, tokens, and currencies through one integration. Build payment applications, trading experiences, and automated financial workflows around what users want to do, rather than the networks and tokens they need to navigate. ## Build with Rhinestone

Smart wallets inside your application, approved with a passkey Payments, swaps, and contract calls funded from any supported chain Funding from wallets, exchanges, and on-ramps, settled where you need it Bank accounts and cards on the same stablecoin balance

## Understand the concepts How funding and execution become one authorized operation How programmable accounts hold assets and enforce authorization How users authorize an account without a password or seed phrase How applications act on a user's behalf within set limits ## Start building Add a passkey wallet to your application Move assets, trade, and call contracts across chains Fund accounts through the widget or the deposit API Endpoints for intents and deposits